Improvement in latches



P. H. BAKER.. Latch.

No. 214,080. Patented April 8, 1879.

WITNESSES INVENTR I ATTORNEYS UNITED STATES PTENT-OTFIGE.-

PETER H. BAKER,y OF SAN FRANCISCO, CALIFORNIA.

I MPROVEM ENT IN LATQHES.

Specification forming part of Letters Patent No. 214,080, dated Aprilv8, 1.879;` application filed December 30, 1878.

construction, as hereinafter setforth. and

shownin the accompanying drawings.

In the drawings, Figure 1 shows the keyhole plate and knob of the lockin position they occupy when applied to 'a door. Fig. 2 is a sectionalelevationof the latch and case, with the parts in position for use as alatch. Fig. 3 is an elevation, showing, the latch locked. Fig. 4 is asection of the fade-plate and end of the case, showing the manner of.connecting the face-plate. Fig. 5 is a cross-section of thevlocking-latch as applied to a door online a:

of Fig. 1. Fig. 6 shows the key made use of to lock the latch.

Similar letters .of reference indicate corresponding parts.'

The case a. is in two parts, which, when placed together, form a hollowcylinder of suitable size and length for containing the operative parts.This form of case can be fitted by simply boring a hole in the edge ofthe door and sinking the'end plate b hush with the edge. To lavoid thenecessityv of using screws the plate b is attached tothe end of case aby a dovetail connection, as shown in Fig. 4. The plate b has a recess,with an undercut edge at opposite sides, asat s, to correspond with thedovetail groove at the sides of lcase a. The twoparts of the case willbe entered in the recess of the plate b, and the case then closedtogetherat the other end, and plate b will then be held securely.

The key-hole plates c c are made concave `and of. circular form, so thatthe central portion,I

where the key-hole d is cutis sunk below the surface of the door, whichrenders it easy to ind the key-hole when there is no light. The

sunken portiouforms a circular projection at' the back of each plate c,that enters a corresponding'depression in the sides of case a.. Theplates cserve to retain the case a 1n place;

and in attaching the plates c to la, door it will be only necessary toturn them around untilthe key-hole d coincides with the hole in case a,and then screw the'plate fast.

e is the latch'and bolt, beveled in the usual manner, and the portionwhich is within case a is slotted to receive the blocking-piece fam-lspiral spring g. The spring g, that forces the latch outward, is placedat the inner end ofthe latch-piece, and is held between the hub h and across-partition, t', that divides the slotof the latch-piece. The piecee passes at the upper and lower side of hub h, and is formed at the endwith two oppositely -inclined surfaces, against which the arms k of hubh act to withdraw the latch.V The hub hhas a square hole for theknob-shank, as usual. A The opening in case a at the forward end, whereblocking-piece fis placed, is of a size and shape to receive and guidethe latch and retain the block f within the slot of the latchpiece, inwhich slot the piecej'is moved back and'forth by the key in locking andunlocking the latch.

l is the tumbler, which is hung to the back part of blockin g-piece f bya pin, m, and moves within a slot in the upper part off. Its forward andmoving end has a T-head, that rests in oneI of the notches n, which areformed at both sides of case a.' A flat spring, secured in the back ofpiece'f, as shown by dotted lines, .serves to retain the tumbler f inthe notches n.

. The blocking-piece f is cut out at o, and formed with a lug, p, andrecesses, in which the wards of the key enterin moving the piece f. Thekey shown in Fig. 6 has double wards, projecting at au angle to eachother, and when entered through the correspondingly-shaped key-hole andturned it iirst raises the end of tumbler l" from the notches n, andmoves the piece f part way forward, the T-head of the tumbler resting onthe ledge between notches n. The second ward then takes against lug pand moves piece f forward until the T end of l drops into the forwardnotches, u, thereby preventing back movement of fand latch e. The latchis then locked, and cannot be operated until unlocked with the key by areversal of the operation described.

By placing the tumbler and blocking-piece.

at the forward end of the. latch the knobs are brought farther from thedoor-post, thereby giving more room to operate them. The latch e can bereversed to suit it for a. right or left lmnrl door.

The advantage over the latch covered b v my Patent No. 194,637 is tha-tI have so simplied it as greatly to reduce the cost of mannfacture.

Having thus described my invention, Ielaim as new and desire to secureby Letters Patent- 1. In combination with the two-part lockcase a,having dovetail grooves, as set forth, the recessed faceplate b, havingundercut edges, substantially as and for the purposes set forth.

2. The combination of the latch e, having at the end oppositely-inclinedsurfaces and partition i, the blocking-piece f, tumbler l, hung by upin, m, in a. notch of said block-piece, the spiral spring g, and thehub h, having arms k, as and for the purpose described.

3. The combination, with the slotted latch e, having notches n, of theslotted blockingpiece f, havin g a flat beek spring, and the tumbler l,having a T-head, the said tumbler being hung to the said piece by a pin,m, as and for the purpose specified.

PETER H. BAKER.

Witnesses:

Joint H. BEHRENS, JOHN T. FERTIG.

